Fig. 2: Association of ELYS with the long arm of the Y complex in X. laevis NR.

a The N-terminal domain of ELYS associates with the long arm of the Y complex in the NR subunit. The outer ELYS (marine) and inner ELYS (purple) associate with the outer and inner Y complexes, respectively. b Structure of the long arm of the inner Y complex. The long arm, spanning a length of ~23 nm, consists of Nup160, Nup37, and ELYS. Inner ELYS from one NR subunit also associates with inner Nup133 from an adjacent subunit. c A close-up view on the interface between the two N-terminal β-propellers of inner ELYS and inner Nup160. d A close-up view on the interface between the α-solenoid of ELYS and Nup37. e A close-up view on the extended interface between the α-helical domain of Nup160 and ELYS. In short, eight helices and three loops from inner ELYS engage in interactions with structural elements from inner Nup160, including seven helices from the inner Nup160 α-helical domain. f A close-up view on the interactions of the C-terminal α-helices of inner ELYS with the C-terminal α-helices of inner Nup85, inner Nup96, and inner Nup160. g A close-up view on the interface between the α-helical domain of inner ELYS and the α-helical domain of inner Nup133 from the adjacent subunit. Helix α10 of inner ELYS closely interacts with the loop between α5 and α6 of inner Nup133. All loops involved in the interaction between nucleoporins are highlighted in thicker form.